Russians are indeed Slavs. They belong to the East Slavic group, which also includes Belarusians and Ukrainians. The Slavic languages, including Russian, are part of the Balto-Slavic branch of the Indo-European language family.14
The genetic studies confirm that Slavic speakers like Russians, Ukrainians, and Belarusians have similar genetic components.1 However, there are some differences in genetic makeup due to historical migrations and interactions with other ethnic groups. For instance, some samples of Novosibirsk residents and Old Believers in Siberia have 5-10% Central Siberian ancestry despite being genetically close to European Slavs.1
It's important to note that while Russians are Slavs, they have a distinct identity and history separate from other Slavic groups. Some Ukrainians, for example, have discourses that emphasize their distinctiveness from Russians, viewing the Russian language as a mixture of Finno-Ugric and Tatar languages with a small Slavic admixture.3 However, this perspective is not shared by all Ukrainians, and the relationship between Ukrainians and Russians remains complex.